Injured passengers are removed from the scene of a train collision and derailment in Connecticut. Two commuter trains leaving about 50 people injured, authorities said. There were no reports of fatalities. (May 17, 2013) Photo Credit: AP

Metro-North South Norwalk to New Haven and Amtrak New York to Boston service remained suspended Saturday morning as investigators began piecing together the cause of the Friday derailment and collision that injured as many as 70 people, at least five of them critically.

Three patients remained in critical condition Saturday morning, with two of those stable, according to officials at two Bridgeport hospitals.

The Metro-North train was leaving the New Haven station bound for Grand Central Terminal when it derailed at 6:32 p.m. Friday, striking a westbound train on the adjacent track, according to Metro-North. The impact knocked several cars from the westbound train off the rails as well. Both trains came to rest on an elevated portion of the track adjacent to I-95 in a busy industrial area of Fairfield.

Connecticut Gov. Dannel Malloy said most of the the injured suffered minor bruises, scrapes and fractures. At least five of the injured were in critical condition and one was in very critical condition, Malloy said during a late Friday news conference. No fatalities have been reported, authorities said.

SERVICE DISRUPTIONS PREDICTED

At least some riders were able to deboard the trains without assistance. New Haven line service has been suspended beyond South Norwalk, with eastbound trains stopping before Fairfield.

Bridgeport Mayor Bill Finch told News12 that damage to the tracks and the ongoing investigation could potentially disrupt transit in the area for days or even weeks. Sections of the track were bent or destroyed by the accident, and Malloy said repair work won't begin until after a complete investigation. Buses were brought in by Metro-North to shuttle stranded passengers to stations closer to their homes and ease traffic around the Fairfield station area, which had become congested with dozens of emergency vehicles, News12 reported.

"Obviously, this is going to have a big impact on the northeast system, including Amtrak," Malloy said at a press conference late Friday night. He said he could not guarantee the New Haven Line would be operating again by Monday morning, and said unrelated repairwork on the line could hamper restoration efforts.

Amtrak, which runs trains with connections on the New Haven Line, announced late Friday through its Twitter feed that service on its northeast corridor trains between New York and Boston were suspended indefinitely due to the derailment and crash.

Authorities said they don't believe there was any foul play involved, and Malloy said there was no indication that the train was targeted in a terrorist incident.

"We have no reason to believe it's anything but an accident," he said, adding that investigators would look at every possibility. "Because there's an investigation we can't rule anything out, but we're certainly not promoting that as the cause."

At Bridgeport Hospital, where 26 of the injured were transported, spokesman John Cappiello said two patients were critically injured, including one person with a facial fracture and another with severe leg injuries.

"The other 24 suffered far less severe injuries ranging from cuts and bruises to perhaps some minor injuries of the extremities, but nothing that could be considered life threatening," Cappiello said.

The nursing supervisor at St. Vincent Medical Center said early Saturday that more than 40 people had been seen and that five patients were admitted, including one in critical condition.

Gregg Baluha, an ArmyNational Guard soldier who was headed to New York City with his young daughter and son, said there was an initial few minutes of confusion as dust clouds from the crash prevented passengers from seeing what was happening outside.

"It seemed like the conductor hit the brakes quite fast, and then we felt an impact," Baluha told News12.

A few minutes later, Baluha said, he could hear sirens getting closer, and soon police and firefighters were outside trying to force the railcar doors open.

About 7000 people were on board the two trains, MTA and Bridgeport officials said.

Aerial images showed the two trains side-by-side, with both leading railcars knocked off their respective tracks, where they came to rest at odd angles. Both trains appeared to consist of the new M8 railcars, which Metro-North introduced on the New Haven Line in 2011 to replace a fleet of aging, 40-year-old model M2 cars. Dozens of emergency workers could be seen west of the tracks, while firefighters checked the interiors of the train cars for any passengers who might have remained aboard after the collision.

Photos snapped by passengers showed seats -- which are bolted into place inside the passenger compartments -- dislodged and torn from their spots, while the impact of the initial collision ripped a hole in the lead car of the Grand Central-bound train, exposing the cabin inside.

FOCUS TURNS TO INVESTIGATION

By late Friday night, Cappiello said some patients were discharged and heading home and volunteers were donating blood. Bridgeport Police Chief Joseph Guadett told the Associated Press that all the wounded had been attended to, and authorities were shifting their focus toward the investigation.

At the scene of the train collision, local fire companies had set up a caravan of engines powering large flood lights so investigators could work through the night. Volunteers from the local Red Cross were on hand providing water and food to first responders who remained on the scene late Friday.

About 112,000 people ride Metro-North trains on the New Haven Line daily, the MTA says. The line runs along a 74-mile stretch from New Haven, Conn., to Grand Central Station in New York City.

The Fairfield Station, the station closest to Friday night's derailment and collision, sits at mile marker 50 and is typically the seventh stop for local New Haven line trains heading west.